This is an example of a new style of opera called opera buffa that emerged during the classical period. it differed from opera in previous periods . it was performed by men; early operas were performed by women.
b. stories were based on greek mythology, and the music was serious and reserved.
c. stories were based on "real people," and the music was light and humorous.
d. stories were based on national heroes, and all vocal solos were recitatives.

Correct answer is 'C'. Stories were based on ''real people,'' and the music was light and humorous

Explanation:

Opera buffa is a genre of opera that used comic characteristics and was developed in the early XVIII century in Naples, then it expander To Rome and northern Italy. It was developed in parallel to opera seria, some of the characteristics of this kind of opera are: it is written in the common language of the town or village where it is going to be presented, it uses common topics or daily life situations, it has very well-known characters or uses characters well known among the attendants. It was made for normal people in comparison to opera seria that was developed for kings and nobility. also in contrast to opera seria, opera buffa had only 2 acts one example of this is ''the barber of seville.''

12-bar blues chorus = a a b